Filler material and method of manufacturing same

ABSTRACT

Down-like synthetic filler material comprises spherical elements or particles made up of filamentary material with a denser concentration of filaments near the surface of the filler elements or particles and provided by an eccentric stream of gas which shapes the filaments into the spherical element.

United States Patent Nishiumi et al.

Dec. 2, 1975 FILLER MATERIAL AND METHOD OF MANUFACTURING SAME Inventors: Shiro Nishiumi; Shoichi Hasegawa,

both of Otsu; Toshiyuki Mizoguchi, Takatsuki; Sachiko Furuta, Otsu, all

of Japan Assignee: Toray Industries, Inc., Tokyo, Japan Filed: Jan. 16, 1974 Appl. No.2 434,907

Related US. Application Data Division of Ser. No. 324,142, Jan. 16, 1973.

US. Cl. 264/89; 156/622; 264/91;

264/93; 264/121; 264/122; 264/128; 264/171 Int. Cl. D04H l/62; D04H 1/74 Field of Search 264/5-8, 14,

References Cited UNITED STATES PATENTS Browne 264/93 Pukacz 264/121 Allman, Jr. et al7 264/14 Davies 161/157 Kranz et al. 161/150 Davies et al. 161/150 Voss et a1. 264/93 Primary Examinerleffery R. Thurlow ABSTRACT 9 Claims, 19 Drawing Figures U3 Patent Dec. 2, 1975 Sheet 1 of4 3,923,942

R U P m A H T PH S SC R R E EE T TT SS OEE YTYY L L Como PC P A009 W NYLON SPHERE w NYLON CYLINDER EE PIQEI WADDING CONTENT, grams Sheet 3 of 4 US. Patfint Dec. 2, 1975 US. Patent Dec 2 1975 Sheet40f4 3,923,942

FILLER MATERIAL AND METHOD OF MANUFACTURING SAME This is a division, of application Ser. No. 324,142, filed Jan. 16, 1973 This invention relates to the filler material used for bedding products e.g. quilts, pillows, etc., wind jackets, sleeping bags, cushions, etc. and to the manufacture and end use of such material.

Down, cotton and synthetic staple fiber has been used as filler for bedding products such as quilts, pillows and so forth wind jackets, sleeping bags, cushions etc.

Among these materials, down shows excellent properties in bulkiness, softness, thermal insulation, compression recovery and moisture transportation. Products such as quilts filled with down conform well to the human body on which it is used, because of the draping property of down-filled products due to the mobility of down in quilts, etc.

Down absorbs and transports water vapor, so that the excellent properties of down are retained even under damp conditions. Down is, however, susceptible to damage by insects and bacteria. On the other hand, so little down is produced in the world that its price is very high.

Cotton, compared with down, is inferior with bulkiness, softness and thermal insulation. Its compression recovery is relatively good, but not under dampe conditions. Cotton is, however, used broadly for the abovementioned products, because of its low price and because of its characteristics in absoring and transporting water vapor.

Synthetic staple fiber is made in a variety of compositions and geometrical shapes due to the wide variability in conditions for its manufacture, so that its properties; e.g., bulkiness, softness and thermal insulating property, are controlled within some range. But, staple fiber of hydrophobic material such polypropylene has a problem as to transportation and absorption of water vapor. Itsbulkiness and compression recovery are relatively good but limited because of the geometrical shape of the fibers in comparison to that of down. Compared with those filled with down, products filled with cotton or conventional synthetic staple fiber do not conform well to the human body on which it is used.

The purpose of this invention is to provide two kinds of synthetic filler material having improved properties and a method for manufacturing such material. This material has especially excellent properties of bulkiness, compression recovery, softness, lightweight, drape or fitting to the wrapped body and thermal insulation as compared to down,

Another purpose of this invention is to provide filler materials which facilitate the production of products e.g. quilts, pillows, wind jackets, sleeping bags, etc., filled with this filler material.

This invention relates to a synthetic filler material, the particles of which consist of round cross-section (spherical and/or cylindrical) bodies, as described below, which bodies are composed of filaments at least 0.2 meters in length running in three dimensional space, having a filament distribution that is denser in the outer layer near the surface of the body and thinner in the inner layer, the filaments being fixed on each other at their points of contact. In these spherical and- /or cylindrical bodies filamentary elements are prevented from intruding into or through other elements 2 and groups thereof when the bodies are compressed or stressed.

This invention also relates to the method manufacturing the above filler materials. This method comprises opening or separating the filaments (which are at least 0.2 m in length) with a gas stream, jetting the filaments into a vessel having some pores on its walls, piling the filaments in it while rotating and shearing (i.e. subjecting to a shearing force) the piled filaments with eccentric gas streams, thus bending the filaments three dimensionally and compressing the filaments on the vessel walls such as the cocoon of a silkworm. After transforming the filamentary mass into a sphere in this manner (as described in detail below) points of contact of the filaments are set and fixed.

In addition, this invention relates to the method manufacturing the cylindrical body material for filler as described above. This method (as described in more detail below) comprises opening or separating filaments with gas stream, jetting the filaments into a cylinder or a tapered tube, bending the filaments three dimensionally, thus transforming the filaments into a cylindrical filamentary mass having a filament distribution that is de'nser in the outer layer near the surface of the body and thinner in the inner layer near the axis of the body, holding the body with pairs of moving belts systems, drafting it if necessary, taking it out, and setting the filaments to fix their points of contact.

By way of background to the present invention, the present inventors investigated the properties and the structure of down which is well known and widely used as an excellent filler material. The results of the investigation are summarized as follows:

A feather of down has a dendroid structure in which several tens of fine branches are developed from the end of a tiny stem or root, and each branch has many tiny twigs or protrusions along both sides of it, making itself barb-like. These branches are so fine and so tender that they bend very easily. Because of these structural features of a leaf of down, the feathers of down are prevented from intrusion or tangling of each element into or with other elements or groups of elements when down is compressed or stressed. Moreover, the branches are substantially bulky due to their barblike structure. Most down feathers are smaller than 25 mm in representative diameter. All of these features of the structure of down feathers help a mass of down to flatten with gentle resistance under compressive force and to easily recover from such force; on the other hand, it allows each feather of down to migrate within their mass.

In contrast, cotton, wool and synthetic staple fiber do not have a branch or barb-like structure so that their masses are easily flattened under compressive action and do not recover as does down.

A brief description of the drawings include:

FIGS. 1 A-D depicting three-dimensional structure of the down produced by the instant invention;

FIG. 2 illustrates an apparatus used in measuring bulkiness of the down;

FIG. 3 graphically illustrates the superiority of the down of the invention as a filler material in bulking or compression behavior and softness;

FIGS. 4 A-C demonstrate the macroscopic migration or mobility of down according to the instant invention;

FIGS. 5 A and B depict the calculation of the density distribution of the down bodies;

FIGS. 6 A-E are a schematic illustration of an example of the manufacturing method of this invention;

FIG. 7 depicts an apparatus for measuring fastness of down bodies under Shearing and compression; and

FIG. 8 illustrates an example of a manufacturing method of this invention.

After many attempts, we reached the conclusion that the structures and shapes shown in FIG. 1 provides the characteristics and three-dimensional structure of down. Shown in FIGS. lA-lD are two round cross-section structures, namely a filamentary spherical body and a filamentary cylindrical body, in which the filaments are arranged three dimensionally, forming a denser outer layer near the surface of the body and a thinner inner layer, and the filaments are set or affixed to each other at their contacting points. Because of these features of the bodies, the bodies are bulky, soft, have high compression recovery and have excellent quality as thermal insulation.

In FIG. 1 A is an outer view of a spherical body (I), FIG. 1B is a cross-sectional view of the spherical objects (I), FIG. 1C is an outer view of a cylindrical body (II), and FIG. 1D is a cross-sectional view of the cylindrical body (II).

To explain the make-up of our invention in more detail, the features of our novel filler are described in comparison with conventional fillers as follows:

FIG. 2 illustrates an apparatus used in determining the bulkiness of various test samples. In FIG. 2 there is shown quilt 1 under evaluation; a sliding scale 2 is used in measuring thethickness or height of quilt 1. This thickness or height is a measure of the bulkiness of the filler in quilt l, and is evaluated as follows:

A sample of filler to be tested is packed into a soft cloth bag, which is 30 cm X 30 cm in dimension and is roughly stitched at 10cm intervals parallel to the edges of the cloth, as seen in FIG. 2. At first, with 50 grams of the filler sample packed evenly into the bag, the thickness or height of the bag is measured by the sliding scale 2 described above. After that, 5.0 grams of filler sample are added to make 100 grams, and the height is again measured. This procedure is repeated until the filler weight is 30.0 grams.

FIG. 3 illustrates graphically the results of this experiment on the bulking properties of various filler material samples. As seen in thisfigure down shows high bulkiness even with a very small amount'of filler and approaches rapidly its final or ultimate height. On the contrary, a sample of synthetic staple fiber, more specifically conventional conjugated crimped polyester staple, gives a curve with a constant, rather linear, increase of height as the amount of packed filler is increased. These curves in FIG. 3 demonstrate the superiority of down as a filler material in comparison to the other conventional filler samples, in bulking or compression behavior and softness. Filler samples of the sphere (I) and the cylindrical body (II) embodiments of our invention each give a curve similar to that of the down.

With the empirical conditions we employed, these curves H(height) vs. M (mass) may be formulated as an empirical equation as follows:

H(m) H.,[l exp (-Cm)], where m is the packed mass of sample in grams; H is the height of the packed model quilt in mm; H... and C are both characteristic constants of the sample which are determined with the quilt cloth being fixed. A larger value of H... indicates a greater limiting or ultimate Table 1 H (mm) C(q") Down 50 0.054 Polyester S.F. 60 .045 Cotton 50 .046 S( l) sphere Nylon 6 55 0.051 S(2) sphere PET* 58 .104 8(3) cylinder Nylon 6 55 .051 S(4) cylinder PET* 55 .072

polyethylene terephthalate The fitting property or conformability of a quilt to the human body is evaluated by sensory observations, e.g, covering a hand or arm model with a test quilt and observing the hollows between the model and the quilt. In any event, to provide a quilt with well-fitting properties, it is desirable to use a filler, the elements of which are mobile in their mass, in which the filler mass is plastic as a whole. To observe this migration behavior of filler elements, a filler sample is packed into the cloth bag described above, and a small amount of colored elements of the filler is placed in the mass near the center of a square containing the mass and the colored elements are surrounded by stitch lines. The sample is then folded ten times on a line through the stitched area and the new location of the colored filler elements is then observed. After folding such a quilt test sample filled with down ten times back and forth along a line on which were located areas containing colored filler elements, as indicated by broken lines in FIG. 4A, the colored elements of down, after the folding action above, were observed to have moved to the areas indicated by solid lines in FIG. 4A, thus demonstrating the macroscopic migration or mobility of down filler elements. In contrast to down, neither conventional synthetic staple nor cotton shows any migration or mobility of elements in a test of the type just described.

Thus, down gives quilts or other similar products which fit or conform well to the human body; in other words, a mass of down' filler is a macroscopically soft plastic material with high bulkiness. Neither conventional synthetic fiber nor cotton shows such fitting behavior or conformability to the human body.

FIG. 4B shows the migration or mobility of the spherical element embodiment of this invention based on a test as described above, and FIG. 4C demonstrates the similar characteristics of the cylindrial element embodiment of this invention in another similar test. As seen in these FIGS. the spherical (I) and the cylindrical (II) bodies of this invention migrate like down and these fillers also provide well-fitting properties or conformability in quilts filled therewith.

It is thought that the reasons for the similar behavior of the spherical and the cylindrical body filler material of our invention to that of down, are:

1. Each element of the filler mass is dependent on each other element but the elements are mutually exclusive i.e. they can not penetrate one another.

2. The outer layer of each filler element is higher in filament density than the inner layer; this results in greater bulkiness per unit weight, greater elastic range and lower or more gentle resistance to compression.

3. The spherical (I) and cylindrical (II) body elements consist of filaments at least 0.2m in length, which are easily bent. This contributes to gentle or mild resistance of the body in compression and gives the body a greater range of elasticity.

4. Because the body of each of the filler elements consists of filaments which are longer than conventional staple, the likelihood of the filament ends protruding from the surface of the body is less than in a mass of staple fibers. This makes the body softer to the touch.

As the material for the spherical and/or cylindrical filamentary bodies of this invention, nylons, polyesters, polyacrylics, poly vinyl alcohols, poly vinylidene chlorides, polyurethanes and polyvinychlorides may be used. Filaments having potential crimping properties may also be used.

The length and fineness of the filaments comprising the spherical and/or cylindrical bodies of the present invention and the diameter, length and bulk density of those bodies are varied depending on the products which contain these bodies as filler,

As to the popular quilts and/or wind jackets for which most down is used, if a filament is finer than 2 denier, the resiliency of the body becomes too low; and if a filament is heavier than 20 denier, the body becomes too hard and too rigid. Thus the fineness of the filament preferably ranges from 2 to 20 denier.

When the diameter of the bodies is smaller than 5 mm, uniformity of body shape is scarcely realized and the body and its collective mass becomes rather nonela-stic; when the diameter is larger than 50mm, the applicable uses are limited into a very narrow range. Therefore, the diameter of the filamentary body of our invention is preferably from 5 mm to 50 mm and most preferably between and 30 mm, which is the range in size of down feathers.

The average bulk density of the spherical and/or cylindrical bodies of our invention is preferably in the range between 1 and 30 mg/cm, and most preferably between 1 and mg/cm. Below a density of 1 mg/cm, the resistance against compression is too low, and above a density of mglcm compression resistance is too high. Thus a product cannot be made in either case. As to the length of the filaments comprising the spherical (I) and/or the cylindrical (II) bodies of our invention, this is different in each manufacturing method as will be described later. Filaments shorter than 0.2 m do not result in a good filler with a low inner density as required in our invention. Filaments longer than 0.2 m make it easier to produce the spherical body (I) of desired density through adjusting the number of filaments forming the yarn that is used and the density of the filaments. For the cylindrical body (II), the filament length is adjusted and determined as to their most desired character for specified end uses.

When the spherical body (I) and/or the cylindrical (II) filler material is used for cushions, thermal insulators, or furniture packing material, the diameter and density of bodies I or II may be increased.

It is desirable to decrease the density at the inner parts of the bodies (I or II). This means that the filaments comprising bodies (I or II) are more concentrated at the outer layer near the surface of the body. As indicated in the round cross-sectional views of the bodies in FIGS. 1B and ID, a large proportion, usually over about of the total of the filaments is preferably located in a layer of the body of from 0.7R to 1.0R from the center of the body, where R is the radius of the body.

As the density of the outer layer of the body (I or II) is decreased and that of the inner layer is increased, then the elastic properties of the body become less desirable.

The density distribution of the bodies of our invention is determined as follows: FIGS. 5A and B are sketches of a speciment of a spherical body (I) and a cylindrical body (II), respectively. From a sample as shown in FIG. 5A, a disc-like specimen is prepared by cutting a body (I) along planes parallel to the equator thereof and spaced a distance 0.2R therefrom where R is the radius of the body (I); a hole having a radius of 0.7R is then bored through the center of the disc by a cutter. The hollow disc specimen thus obtained is weighed. The volume of this specimen is nearly 0.233 that of the shell volume at a distance of from 0.7R to 1.0R from the center of the spherical body (I), according to the following calculation.

0.4R 1r [R 0.7R) ]/(4/3)1r R -(0.7R

More than 80% of the total filament weight is located in the spherical shell described above; if the weight of the hollow disc M is as follows:

0.8M, x 0.233 s M, s M x 0.233

where M is the total weight of the spherical body (I), From the ratio M /M, the density distribution is determined.

In order to determine the proportion of filaments in the 0.7R-1R layer in the case of a cylindrical body (I), a specimen is prepared by slicing the body (II) perpendicular to the body axis, followed by boring a hole of 0.7R in radius, where R is the radius of the body (II); the hollow disc-like specimen thus obtained is weighed. Next the weight ratio M IM is calculated, where M is the weight of the specimen and M is that of original cylindrical body (II) of the same length as the specimen.

The spherical body (I) and cylindrical body (II) is used for quilts and/or garments, where these bodies I or II are subjected to the action of compression and shearing forces. Therefore it is necessary to prevent permanent deformation or disintegration of the bodies (I, II) of the filler material by setting the filaments at their contacting points so that they are fixed. This setting procedure is carried out by applying an adhesive agent at these points, or by heating the body with a thermoplastic polymer at these contacting points. In the latter case, the thermoplastic polymer (III) has a melting point at least 30C below that of the filaments. In the latter case, staple fiber, thermoplastic powder or filaments may be used consisting of the polymer III or such polymer III may comprise the sheath part of conjugate sheath and core-type filaments, and such polymer III may also comprise the one component of at least two components of a side-by-side filament. These thermoplastic materials, such as filaments, made up in part or entirely of polymer III; are blended, in a proportion of at least 30%, with the higher melting point fibers to form bodies (I or II). The difference in thermal shrinkage (between the adhesive and non-adhesive filaments) during heat-setting should be less than 15% in length.

The methods of manufacturing spherical bodies (I) or cylindrical bodies (II) for filler are described as follows:

For (I), filaments longer than 0.2 m in length are opened or separated with a gas stream, jetted into a cylindrical vessel and piled up. After that the piled filaments are sheared and rotated by an eccentric stream of gas in the vessel. As a result, the filaments forming the pile are bent three dimensionally and condensed on a high density layer onto the inner wall of the cylindrical vessel by a centrifugal force due to the rotation thereof and the filament pile is transformed into a spherical body (I), which is then set by fixing the filaments at their contacting points.

FIG. 6 is a schematic illustration of an example of the manufacturing method of this invention. In this figure, filaments 3 are supplied to a nozzle 4. Compressed air 6 is led into nozzle 41 through inlet tube connected to nozzle 4. Thus, filaments 3 are sucked through inlet 7 and ejected pass through outlet 8 into a connecting tube 9 along with the air 6. During this travel, filaments 3 are opened or separated in nozzle 4 under the action of the air stream. After passing into tube 9, the opened filaments are collected in a cylindrical vessel 11 which has pores 10, and the filaments are piled up therein. The piled filaments 12 in the vessel 11 are rotated and sheared by the action of an eccentric stream of air as vessel 11 is shifted to the side, (as seen FIG. 6B) and piled filaments 12 are transformed into a spherical body such as that shown in FIG. 1A. With this rotational motion, filaments are condensed into a denser outer layer due to centrifugal force. Thus the filaments arer bent three-dimensionally, and transformed into a spherical body having a denser outer filament layer than its inner filament layer.

As seen in FIG. 6C, the nozzle 4 and the vessel 11 are positioned or arranged in a parallel but non-coaxial arrangement, so that the piled filaments are exposed to an eccentric flow of air and then rotated and transformed into a spherical body.

As seen in FIG. 60, an additional eccentric flow of air may be supplied from an inlet 14 to piled filaments 112 in vessel Ill, rotating filaments l2 and transforming them into a spherical body.

The methods described above are satisfactorily applied separately or in combination.

To obtain filaments of definite length of more tha 0.2m, such filaments may be cut to a desired length with a conventional cutter tool or cutting device. Such filaments of definite length are then sucked into a nozzle as described above.

However, it is not usually feasible, by conventional mechanical means, to lead the tip end of such cut filaments to the nozzle described above to be sucked therethrough. Therefore, a more practical method is to feed continuous filaments to nozzle 4 and to out these filaments to the desired length as they leave the outlet of the nozzle by an intermittent cutting device.

Nozzle 14 may consist of any means or device that sucks filaments 3 and opens them with an air stream. An air texturizing nozzle is an example of such a device. Pneumatic pressure of from 1 to 5 Kg/cm has been employed in our experiments.

There is, for all practical purposes, no limit in shape or size to the connecting tube that controls the ejected air stream and the opened filaments and ensures their collecting in the cylindrical vessel as a pile.

The collecting vessel must have some pores on its side-wall and a smooth round shaped bottom; typical shapes for such a vessel are shown in FIG. 6E. The size of the vessel is chosen to correspond to the desired sphere size; in general, it is from 5 to 50 mm in inner diameter, and its axis is preferably somewhat longer than its diameter in order to prevent the filaments from flying out of the sphere during rotation. When the sidewalls of said vessel include no pores 10, the jet from nozzle 4 may produce a counterflow interfering with the desired air flow, making piling unsuccessful. For this reason, pores are needed on the side-wall and the bottom of the vessel so that the filaments are smoothly piled up in the vessel while the air is smoothly flowing out through the pores.

The size of the pores is preferably from 1 to 3 mm in diameter, and the area ratio of the total area of all of the pores to that of the total wall is in the range from 5 to 50%.

Air stream 15, rotating the piled filaments 12, as shown in FIG. 6D, may be made eccentric in position by changing the position and/or the angle of the ejecting tube 14. While the pneumatic pressure used in jetting these filaments may be less than 2 kg/cm it may also be intermittent, rather than a continuous flow, which also produces a good shaped spherical body. The period of this intermittent flow may be in the range from 5 X 10 to l X 10 sec.

The method of manufacturing the cylindrical body (II), as illustrated in FIG. 1C, is described as follows:

The filaments are opened with a gas stream and jetted into a cylinder or a tapered tube upon its inner wall, bent three dimensionally, piled up and transformed into a cylindrical filamentary body with a density distribution that is higher in the outer layer and lower in the inner layer in the tube, with the cylindrical body being held by a pair of moving belts in a system or systems; the body is then taken out and is fixed at the contacting points of the filaments, thus producing the cylindrical filamentary body filler material of our invention.

FIG. 8 illustrates an example of the manufacturing method of this invention. In FIG. 8A, filaments l9 supplied by feed roller 20 are delivered to nozzle 21. A compressed air stream 23 is introduced into nozzle 21 through connecting tube 22 attached to nozzle 21. Thus the filaments 19 are sucked into the nozzle inlet 24, ejected with an air stream from the outlet 25 into the tube 26. During this travel, the filaments are opened under the action of the air stream in the nozzle 21, ejected into the tube 26, bent three dimensionally there, piled up there and transformed into a cylindrical filamentary body 31 with an inner layer of low density and an outer layer of higher density. Cylindrical filamentary body 31 is then transferred to a lower belt 27, and held by an upper belt 28, and taken out.

In order to obtain a filament pile having a certain desired average density average bulk density in this process, the filaments 31 are piled in tube 26 to a desired density directly; or, to obtain a higher density, the product of this process is drafted to the desired density. For the latter case, the drafting to the cylindrical body is carried out as follows:

The cylindrical filamentary pile 31, as it emerges from tube 26 is received by a pair of belts 27, 28, as shown in FIG. 8B, and transferred to another pair of belt 29, 30 moving at higher linear velocity than 27, 28. This drafting process may be done once or it may be repeated:

This above process results in a product in which the filaments are bent and transformed into a cylindrical body having an inner layer of lower density than the outer layer.

Again, there is practically no limit in shape or size as to nozzle 21 that sucks filaments and opens them with an air stream. An air texturizing nozzle is one example of a nozzle which may be used. Pneumatic pressure from I to kg/cm has been employed in our experiments.

Similarly, there are essentially no limits as to tube 26. Any tube-like device, which can bend the ejected filaments from the nozzle there dimensionally and cause their piling may be used. It may be a tapered tube or a cylinder as shown in FIG. 8. The diameter of the tube outlet is 5-50 mm, and the length of the tube is 50250 The belts 27, 28 function to take up the piled filaments from tube 26, and to transfer them to the next stage. The clearance between the upper and lower belts 27 and 28 is slightly less than the diameter of the piled cylindrical filamentary body in order to transfer the body smoothly. The material of which belts 27 and 28 are made must have a high frictional coefficient with the filamentary body, to transfer the body without slipping. For example, fuzzed cloth, cloth of spun yarn, and natural and/or synthetic leather may be employed as the belt material.

The cylindrical body (II) thus produced may be used as produced and/or as chopped pieces of some preselected proper length.

The points of contact of the filaments comprising the spherical body (I) or cylindrical body (II) thus obtained may be fixed in any of the following three manners.

The first such manner is a method in which an adhesive agent is sprayed onto bodies I or II for fixing the contact points of the filaments which make up these bodies. Any conventional adhesive agent may be used. For example, silicones and/or acrylic esters are preferable because of their adhesive strength and the softness of the resulting product. These adhesives may be applied in liquid form, as an emulsion or in some other condition. The adhesive should be used in an amount of more than of the filament weight in the bodies of the filler material in order to keep the fastness of bodies I or II.

The second method is as follows: A filamentary or powderedthermo-melting component is blended into the filaments of bodies I or II and the thus-blended body is heated to a temperature above that at which the blended thermo-melting component melts but below that at which the filaments comprising bodies I or II melt, thus fixing the contact points of the filament comprising bodies I or II by melting and re-setting the thermo-melting component. In this case, the melting point of the thermo-melting component is preferably below that of the filaments comprising bodies I or II by 30C or more. If this difference in these melting points is smaller than 30C, the thermo-fixing or setting process might result in the thermal deterioration of the filaments comprising bodies I or II.

If the-filamentary thermo-melting component should contract and cohere in the thermo-fixing process, it might condense to the center of body I or II, resulting in distortion of body I or II. To prevent this result, it is preferable that the thermo-melting filamentary compo- 10 nent be shorter than the peripherial length of body I or II.

Any polymer may be employed as the thermo-melting filamentary component which melts at a temperature below that of the filament comprising body I or II by 30C or more and which is obtained and used either as a filament or a powder. For example, a copolyester of poly-butylene terephthalate-isophthalate and adiphate, nylon 6, nylon 12, nylon 66, nylon 610 and the copolymers of the monomeric constituents of two or more of these polymers may be used.

The thermo-melting filamentary component may be fed and mixed into the filaments used in making bodies I or II, for example, from a sucking nozzle diagonally attached to a connecting tube or tapered tube or in air stream of the filaments.

The third method involves making bodies I or II from a combination of adhesive and non-adhesive filaments and treating these bodies at a temperature above the melting point of the adhesive filament and below that of the non-adhesive filament, thus fixing the contact points of the filaments.

Adhesive filaments, useful in the process just described, may be produced in conventional conjugate filament spinning processes.

The difference in melting points of these components (adhesive and non-adhesive filaments) is preferably greater than 30C for easy control of the process temperature and prevention of thermal deterioration of the high melting non-adhesive component. Both compo-- nents are preferably similar to each other in order to avoid the disengagement of the filaments at their con tacting points. Typical combinations which may be employed are polyethylene terephthalate, poly-butylene.

terephthalate-isophthalate, adipate, copolymer and poly-amide, such as nylon 6, -12, -66, -6l0 and copolymers thereof, and poly acrylonitrile and copolymers thereof, such as methacrylate.

The ratio of adhesive filaments to the total filament content of bodies I or II should be 30% or more, prefen ably 50% or more.

The fastness of bodies I or II under end-use conditions is evaluated as follows: A pre-selected mass of filler material such as bodies I or II is packed in a model cloth bag of IO cm X 10 cm in dimension, and. the packed bag is mounted on the apparatus seen in 'F, shearing and compression is simultaneously applied to bag 17 by the horizontal rotation of the turntable Id attached to this apparatus. A compressive force of 500 g is applied by member 16 to bag 17. After one hour of operation, the filler material is removed from the bag to be observed.

The individual elements or bodies of the tiller mate rial could not be separated due to tangling of filaments between the bodies when the content of the adhesive filaments was less than 30% of the total filaments malting up bodies I or II, and deterioration of the filler was also observed.

When the content of the adhesive filaments was between 30 and 50% of the total filament content in bodies I or II, the filler material was observed to flatten somewhat but the individual elements were still separable from eachother after having conducted the compression and shearing test. The bulkiness and compression recovery of the model quilt with this filler was maintained and its softness was very much increased. Filler made of bodies I or II containing more than 50% 1 1 adhesive filament also maintained the original shape and the good properties of the model quilt.

Filler material bodies I or II containing adhesive filaments cannot be thermo set while keeping the size and shape of bodies I or II constant; generally, bodies I or II become smaller due to the contraction or shrinkage of the adhesive filaments. This is true in general because shrinkage of adhesive filaments is higher than that of non-adhesive ones. If this shrinkage difference should exceed l%, the adhesive filament shrinks so greatly compared to the non-adhesive filament that the former is concentrated into the inner layer of bodies I or II. This results in the formation of an inner layer of high filamentary density in bodies I or II and distortion of bodies I or II. This causes undesirable properties in products made from such material. If this shrinkage difference is less than the increase in density of the inner layer of bodies I or II is so little that the desirable properties of the products made from it are not noticeably affected.

To limit the difference in shrinkage of the adhesive and non-ahesive filaments to less than 10% at the thermosetting condition, when each filament is produced under different conditions of spinning, drawing, ther mo-setting, etc., the adhesive filament is produced by adjusting the content of the low melting component.

The thermo-setting temperature of bodies I or II is higher than the melting point of the low melting component and lower than that of the high melting component filament, and is preferably as low as possible.

Filler material bodies I or II thus obtained, may be treated with lubricating agent and/or antistatic agent, to be able to slip over each other smoothly and to avoid generation of static electricity.

Fibrous of textile products in which filler material comprised of bodies I or II, thus obtained, was packed as filler separately or in combination have excellent properties, much similar to those of the corresponding product made with natural down. Those properties are, namely, excellent bulkiness, light weight, gentle softness, good compression recovery and fitting property or conformality to the wrapped body.

Recommended products in which filler material comprised of bodies I and/or [I may be used as a filler are quilts, pillows, sleeping bags, (and beddings in general), wind jackets, snow wear and so forth. Moreover, filler material, comprised of bodies I and/or Il, may be used as a filler for cushions, packagings, insulating materials, etc.

When conventional cotton or synthetic staple fiber is used for making products such as bedding, such fiber is first converted to a web through a carding process, and these webs are piled up and packed into a lining cloth. In contrast, the filler material of our invention may be randomly packed into a lining cloth without carding and piling for making products such as quilts. The potential for reducing the manufacturing cost of such products is therefore apparent.

In addition, products packed with conventional cotton or synthetic staple fiber filler do not have high compression recovery. Therefore, these products cannot be highly compressed or vacuum packaged for shipping. In storage and transportion therefore, they require a very large space. In contrast, the filler material of our invention, which has excellent compression recovery, may be shipped or stored either in a highly compressed state or vacuum packed. This means a reduction in cost for storage and transportation due to the very small space required.

EXAMPLE I Spherical bodied filler material was made in accordance with the present invention from polyethylene terephthlate filaments as follows:

These filaments were fed into a nozzle 4, actually an air texturizing nozzle, through inlet 7, as shown in FIG. 6A; the filaments were opened with an air stream of 25 kg/cm in pressure and conducted through the connecting glass tube 9 of 150 mm in length and 10 mm in inner diameter, ejected into and piled up in the vessel 11 having forty pores 10 each 2 mm in diameter on its wall and bottom and having a shape of 20 mm in length and 10 mm in diameter. After that, the piled filaments were rotated by an eccentric stream of air as a result of translation of the vessel as shown in FIG. 68. Additionally, an intermittent flow of compressed air of 0.8 kg/cm in pressure with a period of 0.05 second was applied from a glass tube 14 3 mm in inner diameter to the piled filaments as shown in FIG. 6D. Spherical bodies, thus obtained, were taken out, sprayed with a silicone adhesive agent, and thermally set at l80C for 3.0

5 minutes; setting involved fixation of the contact points of the filaments making up the spherical bodies.

The spherical bodies, thus produced, had the appearance of those illustrated in FIG. 1A and had the following properties as listed in Table 2.

Packed products were made with filler material made 0 from samples l-4 respectively; these products had the following features, respectively:

Sample No.

1. low resistance against compression, and low compression recovery.

2. bulkiness and mobility of element similar to down.

as seen in FIGS. 3 and 4B.

3. high resistance against compression, coarse touch.

4. low bulkiness, extremely high resistance against compression.

Filler materials consisting of spherical bodies made from Sample No. (2) were vacuum packed and stored for 22 days, then taken out and allowed to recover for 24 hours. The spherical bodies recovered their original shape by 100%, while the volume recovery of cotton and polyester staple after similar processing as mentioned above is about and respectively.

EXAMPLE 2 Nylon 6 filaments were used to make the materials of out invention as follows:

Sample No. Denier Filaments Length of Filaments (I 100 4 1 meter (2) I 6 1 meter (3) 100 60 l meter Sample No.

1. no satisfactory spherical bodies were produced due to the high bending moment of the filaments.

2., 3. See following table 3 Table 3 Sample No. Diameter of Bulk density Weight ratio sphere (0.7-IR) (2) l8 mm 3.2 mg/cm= 95% (3) 18 3.2 90

The spherical bodies from samples (2) and (3) were collected and packed into a cloth lining to make a separate product with filler. The results were as follows:

Sample No.

2. As seen in FIG. 3, this product showed bulkiness and mobility of elements similar to that of down. After twenty days storage under vacuum the filler recovered its original shape perfectly when unpacked.

3. After twenty days storage in a vacuum package, the filler recovered only 80% of its original shape, .24 hours or more after unpacking.

EXAMPLE 3 As shown in FIG. 8B, polyester filaments were continuously fed to the inlet 24 of an air texturizing nozzle 21 at a velocity of 200 m/min, and opened with a compressed air stream of 2 kg/cm in pressure. The opened filaments were blown into a tapered tube 26, having dimensions of 8 mm top diameter, 16 mm bottom diameter and 20 cm length, bent three dimensionally in said tube, and piled up. Said piled filamentary body, being cylindrical in shape, was delivered to a pair of belts 27, 28 moving at a rate of l m/min, and transported to another pair of belts moving at 4 m/min. The cylindrical body product was thus drafted to four times its original length. Synthetic leather was used as the material of belts 27, 28, 29 and 30. After that, an adhesive agent composed of acrylic esters was sprayed onto said drafted filamentary cylinder, and the product was heated treated at 180C for three minutes, fixing the contact points of the filaments making up the cylindrical filamentary body. The body thus fixed was cut into pieces 3 cm in length.

The cylindrical body product has an appearance as shown in FIG. 1C; its average bulk density was 7.9 mg/cm and its diameter was 14 mm. As seen in FIG. 1B, about of the filaments comprising the body were condensed into the outer layer near the surface of the body between a distance of 0.7R and IR from the center axis of the body, where R is the body radius.

These cylindrical pieces were collected and used as a filler. The products made of this filler showed bulk properties, softness and mobility of filler elements simi lar to that of down as shown in FIG. 3 and FIG. 4C. A product made with this filler was maintained in a vacuum packed condition for 20 days. After that each stress was removed and the specimen recovered its original shape and bulkiness in 24 hours.

EXAMPLE 4 Pieces of a cylindrical filamentary body were manufactured using nylon 6 filaments of 300 Denier and 18 Filament, in a method similar to that of EXample 3; however, a glass tube having dimensions of 15 mm in top inner diameter and 25 mm in bottom diameter was used.

The cylindrical body thus obtained had an average bulk density of 4.0 mg/cm and a diameter of 21 mm. About of the filaments in the body were condensed in the outer layer near the surface of the body at a distance between 0.7R and 1.0R from the center axis of the body, where R is he radius of the body.

Pieces of this cylindrical body product were collected and used as filler. The products made of this filler showed bulk properties, softness and mobility of filler element similar to that of down, as shown in FIG. 3.

EXAMPLE 5 Spherical bodied filler materials were manufactured using nylon 6 filaments (I00 Denier-6 Filaments, 0.1 meter length) using a method as described in Example 2.

On the other hand, a copolyamide made of nylon 6, l2 and 6, 6 melting at C, was spun and drawn into multi-yarn filaments of 20 Denier and 4 filaments, which was used as a thermo-melting component. These filaments were blended into regular nylon as above described in the following manner.

Sample No.

1. Both filaments, nylon 6 and the copolymer of low melting point were sucked into the nozzle simultaneously.

2. The copolymer nylon filaments were cut into pieces of 2 cm in length, the outlet of another suction nozzle was inserted between the nozzle 4 and connecting tube 9, and from the second outlet the cut fibers above were introduced to the apparatus to be blended with the regular nylon filaments.

Spherical bodies of these blended filaments, obtained in the manner described in the previous examples, were heat treated at C for 30 minutes to fix the contacting points of the filaments making up the spherical bodies. The spherical bodies of Sample No. (l) were not perfect spheres but had many peaks and valleys on their surfaces, and 65% of the filaments making up each sphere were condensed in the outer layer near the surface of the body between 0.7R and 1.0R distance from the center of the sphere, where R is the radius of the sphere.

EXAMPLE 6 Several samples of spherical bodies for filler material were made from combinations of the following:

The filaments types shown in Table 4 were combined and made into various blended filament yarns each of 120 denier in fineness but all of varying proportions and shrinkage differences as listed in Table 5. These yarns were then transformed into spherical bodied filler material in the manner of Example 1, and thermally fixed by treatment at 190C for minutes. The material thus obtained was packed into a cloth bag making a quilt model having dimensions of 10 cm X 10 cm. The weight of material packed was 1.0 g, and this quilt model was subjected to the compression and shearing action test described above and illustrated in FIG. 7. The applied load was 500 g, and the time for test was one hour. The results are summarized in Table 5.

Table 5 Content of B Observations before and after testing VII 20% 4.5% After testing, the

spherical bodies were flattened and their filamanets were tangled with each other preventing separation of the spheres. After testing, the spheres were flattened a little,

but spheres were separable as before testing.

After testing, deformation of the spheres was very little. Properties otherwise maintained as those of original.

Before testing. little ups and downs (bumps and depressions) on the sphere surface were observed. The inner layer of filaments in the spherical bodies was of low density.

Before testing, many and sharp ups and downs were observed on the sphere surface. Resistance against compression was high. The inner layer was not of low density.

After testing, substantially no deformation was observed. Properties were maintained as those of the original Same as V1 A. Non-adhesive filaments made of polyethylene terephthalate having a melting point of 260C an a filament fineness of 8 denier.

B. Adhesive filaments consisting of sheath-core type conjugate filaments. The core of these filaments was made of polyethylene terephthalate; the sheath was made of a low melting point component which is a copolymer derived from terephthalic acid, isophthalic acid, and the glycol 1,4 butane diol, having a melting point of C; the sheath-core ratio in these filaments was 3:7 and the filament fineness was 8 denier.

These filament yarns (A and B) were spun and drawn separately, and heat set at various temperatures to control the thermal shrinkage of the filaments. The heat set temperature and shrinkage of the resulting filaments was as follows:

The results in Table 5 show the superiority in dimensional stability and other properties of the filler material of this invention made of blended filaments containing more than 30% adhesive filaments and with a difference in shrinkage between the adhesive and nonadhesive filaments, at the heat set conditions of less than 10%.

We claim:

1. In a method of manufacturing a spherical body useful as a filler material, from a plurality of individual, discontinuous filaments which are at least 0.2 meters in length, the steps which comprise jetting a stream of said discontinuous filaments to open and separate said filaments, directing said filaments into a vessel having vent openings therethrough, causing said filaments to pile up therein, and then causing the piled filaments to bend three-dimensionally by subjecting them to entrainment in a rotating stream of gas which is directed eccentrically with respect to said vessel, said eccentric stream of gas also being directed to force said filaments to be condensed and rotated inside said vessel by centrifugal force into a generally spherical configuration with said filaments contacting each other and concentrated in 17 the area of the surface of the sphere, and thereby transformed into a spherical body, and then adhering said filaments to each other at their contact points.

2. A method as recited in claim 1, wherein the filaments to be opened with an air stream and ejected into the vessel are cut intermittently, to a certain length longer than 0.2 meter and are then ejected into said vessel to be transformed into said spherical body.

3. A method as recited in claim 1, wherein the direction of movement of the filaments is controlled by a connecting tube mounted between the outlet from which said filaments are ejected and said vessel, to control the direction of filament movement into said vessel.

4. A method as recited in claim 1, wherein said filaments are directed eccentrically with respect to said vessel, and said filaments are smoothly rotated and thereby transformed into spheres.

5. A method as recited in claim 1, wherein the said filaments piled up in the vessel are directed eccentrically with respect to said vessel by the translational movement of said vessel with respect to said jet stream and thereby said filaments are transformed into spheres.

6. A method as recited in claim 1, wherein another stream, separate from the stream ejecting said fila- 18 ments, is eccentrically directed toward said filaments in said vessel, and at an angle to the stream first mentioned, and at a pressure to cause said filaments to be rotated by said eccentric stream, and thereby transformed into spheres.

7. A method as recited in claim 1, wherein the contact points of said filaments are adhered by spraying an adhesive fluid onto them, which adhesive is of a nature to adhere said filaments to one another.

8. A method as recited in claim 1, wherein a staple fiber or polymer powder having a melting point at least 30C below the melting point of said discontinuous filaments is blended into said discontinuous filaments, and said discontinuous filaments thermally affixed in spherical form to each other at a temperature below the melting point of said discontinuous filaments and above the melting point of said added staple or powder.

9. A method as recited in claim 7, wherein at least 30% of said filaments are conjugate filaments having a component which has a melting point at least 30 C below that of the remaining filaments, and the filaments of said spherical body are affixed at a temperature between the melting points of said remaining filaments and said low melting component. 

1. IN A METHOD OF MANUFACTURING A SPHERICAL BODY USEFUL AS A FILLER MATERIAL, FROM A PLURALITY OF INDIVIDUAL, DISCONTINUOUS FILAMENTS WHICH ARE AT LEAST 0.2 METERS IN LENGTH, THE STEPS WHICH COMPRISE JETTING A STREAM OF SAID DISCONTINUOUS FILAMENTS TO OPEN AND SEPARATE SAID FILAMENTS, DIRECTING SAID FILAMENTS INTO A VESSEL HAVING VENT OPENINGS THERETHROUGH, CAUSING SAID FILAMENTS TO PILE UP THEREIN, AND THEN CAUSING THE PILED FILAMENTS TO BEND THREE-DIMENSIONALLY BY SUBJECTING THEM TO ENTRAINMENT IN A ROTATING STREAM OF GAS WHICH IS DIRECTED ECENTRICALLY WITH RESPECT TO SAID VESSEL, SAID ECCENTRIC STREAM OF GAS ALSO BEING DIRECTED TO FORCE SAID FILAMENTS TO BE CONDENSED AND ROTATED INSIDE SAID VESSEL BY CENTRIFUGAL FORCE INTO A GENERALLY SPHERICAL CONFIGURATION WITH SAID FILAMENTS CONTACTING EACH OTHER AND CONCENTRATED IN THE AREA OF THE SURFACE OF THE SPHERE, AND THEREBY TRANSFORMED INTO A SPHERICAL BODY, AND THEN ADHERING SAID FILAMENTS TO EACH OTHER AT THEIR CONTACT POINTS.
 2. A method as recited in claim 1, wherein the filaments to be opened with an air stream and ejected into the vessel are cut intermittently, to a certain length longer than 0.2 meter and are then ejected into said vessel to be transformed into said spherical body.
 3. A method as recited in claim 1, wherein the direction of movement of the filaments is controlled by a connecting tube mounted between the outlet from which said filaments are ejected and said vessel, to control the direction of filament movement into said vessel.
 4. A method as recited in claim 1, wherein said filaments are directed eccentrically with respect to said vessel, and said filaments are smoothly rotated and thereby transformed into spheres.
 5. A method as recited in claim 1, wherein the said filaments piled up in the vessel are directed eccentrically with respect to said vessel by the translational movement of said vessel with respect to said jet stream and thereby said filaments are transformed into spheres.
 6. A method as recited in claim 1, wherein another stream, separate from the stream ejecting said filaments, is eccentrically directed toward said filaments in said vessel, and at an angle to the stream first mentioned, and at a pressure to cause said filaments to be rotated by said eccentric stream, and thereby transformed into spheres.
 7. A method as recited in claim 1, wherein the contact points of said filaments are adhered by sprAying an adhesive fluid onto them, which adhesive is of a nature to adhere said filaments to one another.
 8. A method as recited in claim 1, wherein a staple fiber or polymer powder having a melting point at least 30*C below the melting point of said discontinuous filaments is blended into said discontinuous filaments, and said discontinuous filaments thermally affixed in spherical form to each other at a temperature below the melting point of said discontinuous filaments and above the melting point of said added staple or powder.
 9. A method as recited in claim 7, wherein at least 30% of said filaments are conjugate filaments having a component which has a melting point at least 30* C below that of the remaining filaments, and the filaments of said spherical body are affixed at a temperature between the melting points of said remaining filaments and said low melting component. 